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Probing nuclear matter with dileptons

Description: Dileptons are shown to be of interest in helping probe extreme conditions of temperature and density in nuclear matter. The current state of experimental knowledge about dileptons is briefly described, and their use in upcoming experiments with light ions at CERN SPS are reviewed, including possible signatures of quark matter formation. Use of dileptons in an upcoming experiment with a new spectrometer at Berkeley is also discussed. This experiment will probe the nuclear matter equation of stat… more
Date: June 1, 1986
Creator: Schroeder, L. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Design of neutron streak camera for fusion diagnostics

Description: The D-T burn time for advanced laser-fusion targets is calculated to be very short, < 50 ps. We describe the design of a neutron streak camera of 16 ps resolving time that can be used to study the temporal history of fusion burn. The cathode of the neutron streak camera is sensitive to neutrons and is curved such that the difference in the neutron path lengths from a point source to various parts of the cathode is compensated by electron transit times within the streak tube. Thus the cathode ca… more
Date: June 1, 1982
Creator: Wang, C. L.; Kalibjian, R. & Singh, M. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Variations in volatiles in magma bodies based on studies of melt inclusions

Description: Knowledge of volatile concentrations in magmas are important in the prediction of explosive volcanism, and contribute to the understanding of the carbon dioxide budget of the atmosphere. Some important variables that are controlled by volatiles are: crystallization temperature of phases, composition of liquids minimum, and viscosity. Volatiles are also catalysts for reactions.
Date: June 15, 1989
Creator: Vogel, T. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Energy and technology review

Description: Three topics are covered: detecting genetic damage in humans, argon x-ray line imaging, and complete cutoff of Middle Eastern oil. Separate abstracts were prepared for each.
Date: June 1, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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GAMIDEN: a program to aid in the identification of unknown materials by gamma-ray spectroscopy

Description: The intent of the computer code GAMIDEN is to help identify isotopes by their gamma-ray emissions and thus to assist in the nondestructive assay of unknown materials. From both radioactive decays and neutron captures, GAMIDEN searches GAMTOT78, a file of gamma-ray spectra, for matches with observed photon energies. This report describes the search procedure, outlines the use of the code, and gives an example. The code is designed to operate on the CRAY 1 computer at Lawrence Livermore National … more
Date: June 25, 1982
Creator: Howerton, Robert J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Forbidden lines of highly ionized ions for localized plasma diagnostics

Description: Numerous optically forbidden lines resulting from magnetic dipole transitions in low-lying electron configurations of highly ionized Fe, Ti and Cr atoms have been identified in PLT and PDX tokamak discharges, and applied for localized diagnostics in the high-temperature (0.5 to 3.0 keV) interior of these plasmas. The measurements include determination of local ion densities and their variation in time, and of ion motions (ion temperature, plasma rotations) through Doppler effect of the lines. T… more
Date: June 1, 1980
Creator: Hinnov, E.; Fonck, R. & Suckewer, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Identifying heavy Higgs bosons

Description: Two techniques for identifying heavy Higgs bosons produced at SSC energies are discussed. In the first, the Higgs boson decays into ZZ, with one Z decaying into an e-pair or ..mu..-pair and the other into a neutrino pair. In the second, the production of the Higgs boson by WW fusion is tagged by detecting the quarks that produced the bremsstrahlung virtual W's. The associated Higgs decay is identified by one leptonic and one hadronic decay. Both methods appear capable of finding a heavy Higgs b… more
Date: June 1, 1986
Creator: Cahn, R.N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Application of adjusted data in calculating fission-product decay energies and spectra. [ADENA code]

Description: The code ADENA, which approximately calculates fission-product beta and gamma decay energies and spectra in 19 or fewer energy groups from a mixture of /sup 235/U and /sup 239/Pu fuels, is described. The calculation uses aggregate, adjusted data derived from a combination of several experiments and summation results based on the ENDF/B-V fission-product file. The method used to obtain these adjusted data and the method used by ADENA to calculate fission-product decay energy with an absorption c… more
Date: June 1, 1982
Creator: George, D. C.; LaBauve, R. J. & England, T. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Experimental studies of actinides in molten salts

Description: This review stresses techniques used in studies of molten salts containing multigram amounts of actinides exhibiting intense alpha activity but little or no penetrating gamma radiation. The preponderance of studies have used halides because oxygen-containing actinide compounds (other than oxides) are generally unstable at high temperatures. Topics discussed here include special enclosures, materials problems, preparation and purification of actinide elements and compounds, and measurements of v… more
Date: June 1, 1985
Creator: Reavis, J.G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Array analysis of regional Pn and Pg wavefields from the Nevada Test Site

Description: Small-aperture high-frequency seismic arrays with dimensions of a few kilometers or less, can improve our ability to seismically monitor compliance with a low-yield Threshold Test Ban Treaty. This work studies the characteristics and effectiveness of array processing of the regional Pn and Pg wavefields generated by underground nuclear explosions at the Nevada Test Site. Waveform data from the explosion HARDIN (m{sub b} = 5.5) is recorded at a temporary 12-element, 3-component, 1.5 km-aperture … more
Date: June 1, 1991
Creator: Leonard, M.A. (California Univ., Berkeley, CA (United States). Dept. of Geology and Geophysics Lawrence Berkeley Lab., CA (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermal behavior of dawsonite

Description: Evidence for the dawsonite decomposition reaction sequence is presented. Synthetic dawsonite was heated at temperatures from 250 to 800/sup 0/C and studied by X-ray powder diffraction and infrared spectroscopy. From 350 to 550/sup 0/C sodium carbonate and a low temperature form of alumina were the main products. Hydrolysis experiments showed that this heretofore unidentified alumina product is rho-alumina. At temperatures of 600/sup 0/C and above, the sodium carbonate and rho-alumina react in a… more
Date: June 1, 1980
Creator: Keenan, F J; Howatson, J & Smith, J W
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurements of cross sections relevant to. gamma. -ray line astronomy

Description: Gamma-ray production cross sections have been measured for the ..gamma..-ray lines which are mostly strongly excited in the proton bombardment of C, O, Mg, Si, and Fe targets of natural isotopic composition. High resolution germanium detectors were used to collect ..gamma..-ray spectra at proton bombarding energies of 20, 30, 33, 40 and 50 MeV. 6 refs., 6 figs.
Date: June 1, 1986
Creator: Lesko, K.T.; Norman, E.B.; Larimer, R.M. & Crane, S.G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Energy and technology review

Description: Brief reviews are presented of research programs at Lawrence Livermore Laboratory. In one, fast and precise measurement techniques to meet the demanding specifications for microsphere targets used in inertial-confinement fusion experiments are described. Another program is described in which a Raman-spectroscopy microprobe is used to perform molecular-structure analyses on submicron-size particles. Finally, the first year of the controlled thermonuclear reactions program is described. (GHT)
Date: June 1, 1982
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Neutron and hard x-ray measurements during pellet deposition in TFTR

Description: Measurements of neutrons and hard x rays are made with a pair of plastic scintillators during injection of deuterium pellets into deuterium TFTR plasmas. Three cases are investigated. During ohmic heating in plasmas with few runaway electrons, the neutron emission does not increase when a pellet is injected, indicating that strong acceleration of the pellet ions does not occur. In ohmic plasmas with low but detectable levels of runaway electrons, an x-ray burst is observed on a detector near th… more
Date: June 1, 1986
Creator: Heidbrink, W. W.; Milora, S. L.; Schmidt, G. L.; Schneider, W. & Ramsey, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Estimated neutron-activation data for TFTR. Part II. Biological dose rate from sample-materials activation

Description: The neutron induced material activation dose rate data are summarized for the TFTR operation. This report marks the completion of the second phase of the systematic study of the activation problem on the TFTR. The estimations of the neutron induced activation dose rates were made for spherical and slab objects, based on a point kernel method, for a wide range of materials. The dose rates as a function of cooling time for standard samples are presented for a number of typical neutron spectrum ex… more
Date: June 1, 1982
Creator: Ku, L. & Kolibal, J.G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Subthreshold K/sup -/ Production in Nucleus-Nucleus Collisions

Description: We have measured the production cross section and momentum distribution of K/sup -/ produced at 0/sup 0/ in /sup 28/Si + /sup 28/Si collisions at an energy of 2.1 GeV/nucleon. The K/sup -/ spectrum is approximately exponential. The large yield in the subthreshold production of K/sup -/ that we observe corresponds to a production rate of 1K/sup -/ per 50 collisions at impact parameters less than 1f. Productions mechanisms involving collective effects and thermal equilibration are discussed.
Date: June 1, 1983
Creator: Shor, A.; Carroll, J. & Barasch, E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Search for Single Photons From Radiative Neutrino or Supersymmetric Particle Production

Description: Final results are presented from a search for single-photons produced in association with neutrinos or other weakly interacting neutral particles in e/sup +/e/sup -/ annihilations at ..sqrt..s = 29 GeV. The search was performed with the MAC detector at PEP in a total integrated luminosity of 177 pb/sup -1/. The search limits the number of light-neutrino families to N/sub nu/ < 16. The mass of the selectron is limited to m/sub e tilde/ > 50 GeV/c/sup 2/ if m/sub e tilde L/ = m/sub e tilde R/ and… more
Date: June 1, 1986
Creator: Ford, W. T.; Camporesi, T.; Hurst, R. B.; Band, H. R.; Ash, W. W.; Chadwick, G. B. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Wolter x-ray microscope calibration

Description: A 22 x Wolter microscope was calibrated after several months of operation in the Lawrence Livermore National laboratory (LLNL) Inertial Confinement Fusion program. Placing a point x-ray source at the microscope focus, I recorded the image plane spectrum, as well as the direct spectrum, and from the ratio of these two spectra derived an accurate estimate of the microscope solid angle in the 1 to 4 keV range. The solid angle was also calculated using the microscope geometry and composition. Compa… more
Date: June 1, 1986
Creator: Gerassimenko, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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CARBON-13 NMR STUDIES OF LIQUID CRYSTALS

Description: High resolution, proton decoupled {sup 13}C nmr are observed for a series of neat nematic liquid crystals, the p-alkoxyazoxybenzenes, and a smectic-A liquid crystal, diethylazoxydibenzoate in a magnetic field of 23 kG. The (uniaxial) order parameters S = &lt;P{sub 2}(cos{theta})&gt; are found to be about 0.4 and 0.9 for the nematic and smectic-A phase respectively at the clearing points. The order parameter increases with decreasing temperature in the nematic phase but is constant, or nearly so… more
Date: June 1, 1975
Creator: Allison, Stuart
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Sigma: Web Retrieval Interface for Nuclear Reaction Data

Description: The authors present Sigma, a Web-rich application which provides user-friendly access in processing and plotting of the evaluated and experimental nuclear reaction data stored in the ENDF-6 and EXFOR formats. The main interface includes browsing using a periodic table and a directory tree, basic and advanced search capabilities, interactive plots of cross sections, angular distributions and spectra, comparisons between evaluated and experimental data, computations between different cross sectio… more
Date: June 24, 2008
Creator: Pritychenko,B. & Sonzogni, A.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Vibration Measurements to Study the Effect of Cryogen Flow in Superconducting Quadrupole.

Description: The conceptual design of compact superconducting magnets for the International Linear Collider final focus is presently under development. A primary concern in using superconducting quadrupoles is the potential for inducing additional vibrations from cryogenic operation. We have employed a Laser Doppler Vibrometer system to measure the vibrations in a spare RHIC quadrupole magnet under cryogenic conditions. Some preliminary results of these studies were limited in resolution due to a rather lar… more
Date: June 25, 2007
Creator: He, P.; Anerella, M.; Aydin, S.; Ganetis, G.; Harrison, M.; Jain, A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Unified Model of Dynamic Forced Barrier Crossing in Single Molecules

Description: Thermally activated barrier crossing in the presence of an increasing load can reveal kinetic rate constants and energy barrier parameters when repeated over a range of loading rates. Here we derive a model of the mean escape force for all relevant loading rates--the complete force spectrum. Two well-known approximations emerge as limiting cases; one of which confirms predictions that single-barrier spectra should converge to a phenomenological description in the slow loading limit.
Date: June 21, 2007
Creator: Friddle, R W
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Direct Observation of the Kinetically Relevant Site of CO Hydrogenation on Supported Ru Catalyst at 700 K by Time-Resolved FT-IR Spectroscopy

Description: Time-resolved FT-IR spectra of carbon monoxide hydrogenation over alumina-supported ruthenium particles were recorded on themillisecond time scale at 700 K using pulsed release of CO and a continuous flow of H2/N2 (ratio 0.067 or 0.15, 1 atm total pressure). Adsorbed carbon monoxide was detected along with gas phase products methane (3016 and 1306 cm-1), water (1900 +- 1300 cm-1), and carbon dioxide (2348 cm-1). Aside from adsorbed CO, no other surface species were observed. The rate of formati… more
Date: June 4, 2008
Creator: Frei, Heinz; Wasylenko, Walter & Frei, Heinz
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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